In addition to the characterization of heritable disorders of collagen metabolism, we are attempting to characterize the biochemistry of membrane bound collagens in human fibroblasts. The objective of this study is to delineate biochemical defects and to correlate the clinical characteristics with the biochemical defects in heritable disorders of collagen metabolism. In the next year we intend to develop and assay for procollagen peptidase, the enzyme which converts procollagen to collagen, and to examine various human diseases which might have defects in this enzymatic conversion. BIBLIOGRAPHIC REFERENCES: Defects in the Biochemistry of Collagen in Diseases of Connective Tissue. Juoni Uitto and Jack R. Lichtenstein. J. of Invest. Derm., Feb., 1976.